Looking like a stellar sea turtle, the galaxy known as NGC 6240 is actually the result of two smaller galaxies that started merging 30 million years ago.

The collision triggered a bout of star formation and sparked numerous supernova explosions. X-ray images of the peculiar galaxy also revealed two giant black holes about 3,000 light-years apart that will eventually join together.

NGC 6240 sits about 400 million light-years away in the constellation Ophiuchus.